— People who want to keep their current insurance will be automatically re-enrolled, if the plan is available.

— For most, the government will re-estimate the amount of subsidies that work to reduce their premiums. That's if people checked a box on their original application allowing HealthCare.gov to access their latest tax data.

Consumers will start getting notices about their options before the Nov. 15 start of the next open enrollment season.

"We are committed to simplifying the experience for consumers by allowing auto-enrollment," Burwell said in a statement. That means smoothing out the process for people who haven't had big changes in income, family circumstances or residence.

Millions more Americans are expected to try HealthCare.gov for the first time next year. Making things easier for those already signed up cuts the workload for federal and state insurance websites, reducing the odds of another round of headline-grabbing computer crashes.

But premiums will be changing for 2015, and an independent market analysis firm is advising consumers to shop around to make sure they are getting the best deals.

Avalere Health released an analysis of proposed premiums next year in a sample of states, and found the changes sufficiently large to impact subsidies in six out of nine. That's because subsidies are tied to the price of a low-cost benchmark plan in each state. Avalere concluded that consumers should weigh the pros and cons of keeping their current plan and providers versus lower premiums.